Electric switch.



UNITED STATES.

PATENT OFFICE.

GEORGE E. THOMAS, OF HARTFORD, CONNECTICUT, ASSIGNOR TO THE PERKINS ELECTRIC SWITCH MANUFACTURING COMPANY, OF SAME PLACE.

ELECTRIC SWITCH.

SPECIFICATION formingpart of Letters Patent No. 681,353, dated August 27, 1901. Application fil'ed March 5, 1901. Serial No 49,874. (No model.)

To all whom it mat concern.- I Be it known that I, GEORGE B. THOMAS, a citizen of theUnited States of America, residing in Hartford, county of Hartford, State of Connecticut, haveinvented Improvements in Electric Switches, of which the following is a specification.

The object of my invention is to construct a simple and efficient electric switch with as few moving parts as possible.

In the accompanying drawings I have shown my invention as embodied in the form of a two-push button electric switch, and while my improvements have been designed more particularly with reference to a switch of that character features of my invention are applicable to other constructions of electric switches. I would further observe that while I have in the drawings shown my invention as applied to a double-pole switch I do not wish to confine myself thereto, as my invention is equally applicable to single-pole or three-pole switches, oreven to switches with a greater number of poles than four.

In the accompanying drawings, Figure 1 is a longitudinal section of a switch constructed in accordance with my invention, the section being taken on the line 1 1, Fig. 2. Fig. 2 is a plan view of the switch with the face-plate off and the push-buttons detached. Fig. 3 is a transverse section on the line 3 3, Figs. 1 and2. Fig. 4. is a transverse section on the line l 4, Figs. 1 and 2. Fig. 5 is an enlarged view of the operative parts of the switch detached from the receptacle. Fig. 6 is a perspective view of a detail, and Fig. 7 is an enlarged sectional view of a detail.

The receptacle or inclosing case R, of porcelain or other suitable insulating material, is provided with theusual face-plate P, which may be conveniently secured in place by securing-screws entering the metal lugs N, which are in turn secured to the edges of the receptacle R by screws 11., introduced from the back. At the innercorners of the receptacle are pillars r, and between these pillars and the walls are apertures r, leading from the back to the front of the receptacle for the conductors, the baredends of which are to be electrically and mechanically secured to the metallic binding-posts B. These bindingposts are U -shaped, as shown more clearly in Figs. 4 and 6, and are secured to the tops of pillars r in the inner corners of the receptacle by means of screws 1 introduced from the back of the case, Fig. 1, these screws ontering one of the legs of the U shape. The other leg of the U shape has passing through it a binding-screwb for the conductor end.

Between the binding-post B and the top of each pillar r I clamp an L-shaped piece C C, and these pieces form the fixed contacts with which cooperate the moving poles or contacts hereinafter described. These fixed contacts are made separately from the binding-post B to prevent the contacts being slewed around in screwing up the screws r or b, and to make the contacts self-adjusting when the parts of the switch are put together I make these contacts C with elongated slots 0, Fig. 6. In fitting the parts together these contacts 0 and binding-posts B are mounted on the pillars r by their screws r without special care being required as to the positions occupied by I the contacts 0 O, and then when the operative parts of the switch are put in place the contacts 0 C can be adjusted to their proper positions or can be made, as it were, self-adjusting by bringing the moving part of the switch into the closed position. Then when these contacts C C have been adjusted the screws r are tightened up. I prefer to form in the body of the case a partition-wall W between the adjacent contacts C C, Figs. 2

and I.

Referring now to the operative parts of the switch, they comprise a fixed frame, a slide carrying the moving contacts, an oscillating catch-lever actuated by the push-buttons or other means, and a single spring.

The frame D, which in the present instance is shown as secured in the bottom of the receptacle R by screws or otherwise, is prefer ably of the rectangular form illustrated in Fig. 3 and may conveniently be formed of a sheet- ,metal plate bent to form the ends (1 d and one side cl, while the fourth side of the frame is formed by a connecting-rod d This side at has formed in it two guiding-slots e 6', Figs. 1 and 5. The slide F, which carries the contacts G G, is guided in this frame D and is preferably formed of a front plate f,with outwardly-bent fingers or lugs 3 and 4 projecting through and guided in the slots 6 e of the receptacle,while a back plate f ',with outwardlybent lugs 5 5, is guided on the bar (1 of the frame D. Between the front and back plates ff of the slide I clamp spring-fingers G G, which constitute the moving contacts cooperating with the fixed contacts 0 O in the receptacle B, one pair of contacts G being of course insulated from the other pair of contacts G by suitable insulating material 9. I prefer to separate the electrical contact-plates G and G from each other by means of disks or sheets of mica compressed together, as shown at m, between the said plates G G, Fig. 7, insulating thimbles 21 being fitted over the clamp ing-bolts 22. The slide F also has a finger 6 (which may be stamped out as part of the front plate f for the action of the legs .9 s of the spring S, coiled around the center post'P.

The oscillating catch-lever before referred to is shown as consisting of a bar or plate H, pivoted to oscillate on a center post Pin the frame D and having a finger '7 projecting backward toward the frame D and acted on oscillating lever 11, one of these catches 10 being adapted to cooperate with the lug 3 on the front plate of the slide F, while the o'ther, 11, is adapted to cooperate with the other lug 4 at the opposite end of the same plate of the I slide F.

The push-buttons K have their bent legs 7a;

7: pivotally connected to the opposite ends of tion to the other, Figs. 1 and 5. make the faces of the push-buttons concave,

as illustrated in Fig. 1, to counteract a tendency of the operators finger to slide off the button, as is common where the head of the button is of convex form, as is usual.

The operation of the switch is as follows: Supposing the switch to be closed, as illustrated in Fig. 1, the catch 11 of the oscillating lever H will engage behind the lug at of the slide F at one edge of the said lug, insuring the retention of the slide in the position shown with the switch closed. To move the slide back to carry the moving contacts or poles G G away from the fixed poles C O to break the circuit, the outwardly-projecting button at the upper part of Fig. 1 will be pressed in, rocking the lever H over to the position slightly beyond that shown by dotted lines in Fig. 5, and thereby moving the catch 11 across back of the lug 4 until it passes beyond the latter. The movement of the lever has at the same time tensioned the spring S by the finger 7 of the lever carrying the leg s of the spring forward, while the other legs is meanwhile held back by the finger 6 on the slide. When, therefore, the movement of the lever carrying the catch 11 releases the slide, the leg 5' of the spring will instantly press the slide from the position shown in Fig. 1 to the position shown 'in Fig. 5 with a quick snap movement, making an efiective break of the circuits. The relation of the parts to each other is such that on releasing the fingerpres'sure from the button which has been pressed down the spring S will rock the oscillating lever slightly backward to engage the catch 10 with the back of the lug 3 on the slide F, as illustrated in Fig. 5, so that thereafter the slide carrying the moving contacts can only move back again to close the circuit when the lever H has been moved again from the position shown in Fig. 5 to that shown in Fig. l, causing once more the tensioning of the spring S and the release of the slide from the catch 10, as will be understood.

From the foregoing description it will be seen that, excepting the push-buttons, the only moving parts are the slide, the oscillating catch-lever, and the one spring.

I claim as my invention-- 1. An electric switch in which are combined a case with fixed contacts, a frame, a contact-carrying slide guided in the frame, a single spring to act on the slide, an oscillat ing catch-lever to hold the slide, while the lever is oscillated to tension the spring, and then to release the slide by the further-oscil lation of the lever.

2. An electric switch in which are com bined a case having fixed contacts, a frame, a contact-carrying slide guided in the frame and having two lugs with a spring to act upon the slide, an oscillating lever having two catches to cooperate with the said lugs to hold the slide while the lever is being oscillated to tension the spring and then to release the slide.

3. An electric switch in which are combined a frame, an oscillating catch-lever and a spring adapted to be tensioned by the lever and a slide to be held and released by the catch lever while the latter tensions the spring, the said slide having front and back plates with lugs guided by the frame.

4. In an electric switch, the combination of a frame having guide-slots on one side and a guide-bar on the other side with a contactcarrying slide having front and back plates, one plate being provided with lugs guided in the slots and the other plate having lugs guided on the rod of the frame, substantially as described.

5. In an electric switch, the combination of a frame with a slide having lugs guided by the frame, an oscillating lever having catches .to engage with said lugs and a spring to be 6. An electric switch having a receptacle name to this specification in the presence of with insulating pillars and contacts moulliter} two subscribing witnesses. t ereon and. with apertures 1' in the wal s 0 the receptacle behind the pillars and leading GEORGE THOMAS 5 from the back to the front of the receptacle, Witnesses:

substantially as described. G. W. GOODRIDGE,

In testimony whereof I have signed my W'. B. COVIL; 

